Light-emitting substrate and manufacturing method therefor, and display apparatus
By setting a reflective part on the light-emitting substrate, the thickness of the reflective part is related to the light intensity, which solves the problems of increased backlight module thickness and uneven brightness, and achieves a more uniform light source and lower power consumption.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- BOE TECHNOLOGY GROUP CO LTD
- Filing Date
- 2026-01-04
- Publication Date
- 2026-07-30
AI Technical Summary
In existing technologies, backlight modules need to be equipped with multiple light-diffusing film layers to achieve uniform light sources, which leads to increased module thickness and reduced light efficiency. Furthermore, the thickness consistency of the reflective layer is difficult to control, which can easily result in uneven brightness.
A reflective part is set on the light-emitting substrate. The side of the reflective part away from the diffuser plate is convex. The thickness is positively correlated with the light intensity of the light-emitting unit. The pattern is formed by 3D printing or halftone masking. The reflective part has the largest thickness at the axis of symmetry perpendicular to the substrate, so that more reflection and absorption are achieved in areas with stronger light intensity and less reflection in areas with weaker light intensity.
It improves the light uniformity of the light-emitting substrate, reduces the number of light uniform films or diffusion films, reduces the thickness and cost of the light-emitting substrate, and at the same time improves luminous efficiency and reduces power consumption.
Smart Images
Figure CN2026070172_30072026_PF_FP_ABST
Abstract
Description
Light-emitting substrate and its preparation method, display device
[0001] Cross-references to related applications
[0002] This application claims priority to Chinese Patent Application No. 202510121567.2, filed on January 24, 2025, entitled "Light-emitting substrate and method for preparation thereof, display device", the entire contents of which are incorporated herein by reference. Technical Field
[0003] This disclosure relates to the field of display technology, and in particular to light-emitting substrates and their preparation methods, and display devices. Background Technology
[0004] Mini LED (Mini Light Emitting Diode) technology is known for its high brightness. When applied to backlight modules and display devices, Mini LED technology allows for more precise control of the backlight using local dimming technology, achieving high resolution and high contrast displays and significantly improving display quality. Summary of the Invention
[0005] This disclosure provides a light-emitting substrate and its preparation method, as well as a display device, to improve the light uniformity of the light-emitting substrate.
[0006] This disclosure provides a light-emitting substrate, which includes:
[0007] Base;
[0008] Multiple light-emitting units are located on one side of the substrate;
[0009] A diffuser plate is located on the side of the multiple light-emitting units that faces away from the substrate;
[0010] Multiple reflective parts are located on the side of the diffuser plate facing multiple light-emitting units or on the side of the diffuser plate away from the substrate; one light-emitting unit corresponds to one reflective part; the surface of the reflective part away from the diffuser plate is a convex surface that protrudes towards the side away from the diffuser plate; the reflective part has the greatest thickness at the axis of symmetry perpendicular to the substrate.
[0011] In some embodiments, the orthographic projection of the light-emitting unit onto the substrate is located within the orthographic projection of the reflective portion onto the substrate, and the axis of symmetry of the reflective portion perpendicular to the substrate coincides with the axis of symmetry of the light-emitting unit perpendicular to the substrate.
[0012] In some embodiments, the thickness of the reflective portion at different locations is positively correlated with the light intensity emitted by the light-emitting unit to different locations of the reflective portion.
[0013] In some embodiments, the maximum thickness of the reflective portion is greater than or equal to 5 micrometers and less than or equal to 30 micrometers, and the reflectivity corresponding to the maximum thickness of the reflective portion is greater than or equal to 50% and less than or equal to 80%.
[0014] In some embodiments, the shape of the orthographic projection of the reflective portion onto the substrate is similar to the light emission pattern of the light-emitting unit.
[0015] In some embodiments, the reflective portion includes a negative photosensitive reflective material.
[0016] In some embodiments, the light-emitting substrate further includes:
[0017] The diffusion layer is located on the side of the diffusion plate away from the multiple reflective parts.
[0018] In some embodiments, the haze of the diffusion layer is greater than or equal to 50% and less than or equal to 90%; the transmittance of the diffusion layer is greater than or equal to 50% and less than or equal to 95%; and the thickness of the diffusion layer is greater than or equal to 5 micrometers and less than or equal to 100 micrometers.
[0019] In some embodiments, the light-emitting substrate further includes:
[0020] An adhesive structure is located between the diffuser plate and the substrate; the orthographic projection of the adhesive structure onto the substrate surrounds the orthographic projections of multiple light-emitting units onto the substrate; the adhesive structure includes multiple through-holes penetrating the adhesive structure in a direction parallel to the substrate.
[0021] This disclosure provides a method for preparing a light-emitting substrate, comprising:
[0022] Provide a substrate, and arrange multiple light-emitting units on one side of the substrate;
[0023] A diffuser plate is provided, and a pattern of multiple reflective portions is formed on one side of the diffuser plate; the diffuser plate and the multiple reflective portions are located on the side of the light-emitting unit away from the substrate; the multiple reflective portions are located on the side of the diffuser plate facing the multiple light-emitting units or on the side of the diffuser plate away from the substrate; one light-emitting unit corresponds to one reflective portion; the surface of the reflective portion on the side away from the diffuser plate is a convex surface that protrudes towards the side away from the diffuser plate; the thickness of the reflective portion is the greatest at the axis of symmetry perpendicular to the substrate.
[0024] In some embodiments, a pattern of multiple reflective portions is formed on one side of the diffuser plate, specifically including:
[0025] A negative photosensitive reflective material layer is formed on the side of the diffuser plate opposite to the multiple light-emitting units;
[0026] Multiple light-emitting units are lit up, and the negative photosensitive reflective material layer is exposed using these multiple light-emitting units;
[0027] The negative photosensitive reflective material layer is developed to form a pattern of multiple reflective parts.
[0028] In some embodiments, a pattern of multiple reflective portions is formed on one side of the diffuser plate using 3D printing or halftone masking.
[0029] In some embodiments, the method further includes:
[0030] An adhesive material is coated onto the substrate to form an adhesive structure; the orthographic projection of the adhesive structure onto the substrate surrounds the orthographic projection of multiple light-emitting units onto the substrate.
[0031] The diffusion plate is bonded to the substrate using an adhesive structure;
[0032] Multiple through-holes are formed in the direction parallel to the substrate, penetrating the bonding structure.
[0033] In some embodiments, the method further includes:
[0034] A diffusion layer is formed on the side of the diffuser plate that is away from the multiple reflectors.
[0035] This disclosure provides a display device comprising:
[0036] The light-emitting substrate provided in the embodiments of this disclosure;
[0037] The display panel is located on the light-emitting side of the light-emitting substrate.
[0038] The light-emitting substrate and display device provided in this disclosure increase light utilization and improve the uniform light effect of the light-emitting substrate by providing a reflective portion. Furthermore, the surface of the reflective portion facing away from the diffuser plate is a convex surface that protrudes towards the side facing away from the diffuser plate, and the reflective portion has the greatest thickness at the axis of symmetry perpendicular to the substrate, i.e., the reflective portion has a shape that is thicker in the middle and thinner at the edges. In this way, when light emitted from the light-emitting unit passes through the reflective portion, more light in areas with higher light intensity is reflected and absorbed by the reflective portion, while less light in areas with lower light intensity is reflected and absorbed by the reflective portion. This increases luminous efficacy and makes the emitted light brightness of the light-emitting substrate more uniform, further improving the uniform light effect of the light-emitting substrate. This significantly reduces the number of light-diffusing films or light-uniforming films in the light-emitting substrate, thereby reducing the thickness of the light-emitting substrate and lowering costs. Moreover, the increased luminous efficacy of the light-emitting substrate also reduces power consumption. Attached Figure Description
[0039] To more clearly illustrate the technical solutions in the embodiments of this disclosure, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0040] Figure 1 is a schematic diagram of the structure of a light-emitting substrate provided in an embodiment of this disclosure;
[0041] Figure 2 is a schematic diagram of another light-emitting substrate provided in an embodiment of this disclosure;
[0042] Figure 3 is a schematic diagram of another light-emitting substrate provided in an embodiment of this disclosure;
[0043] Figure 4 is a schematic diagram of another light-emitting substrate provided in an embodiment of this disclosure;
[0044] Figure 5 is a schematic diagram of another light-emitting substrate provided in an embodiment of this disclosure;
[0045] Figure 6 is a schematic diagram of another light-emitting substrate provided in an embodiment of this disclosure;
[0046] Figure 7 is a schematic diagram of another light-emitting substrate provided in an embodiment of this disclosure;
[0047] Figure 8 is a schematic diagram of another light-emitting substrate provided in an embodiment of this disclosure;
[0048] Figure 9 is a schematic diagram of another light-emitting substrate provided in an embodiment of this disclosure;
[0049] Figure 10 is a schematic diagram of another light-emitting substrate provided in an embodiment of this disclosure;
[0050] Figure 11 is a schematic diagram of another light-emitting substrate provided in an embodiment of this disclosure;
[0051] Figure 12 is a graph showing the relationship between the normalized brightness and position of the light-emitting substrate provided in the embodiments of this disclosure;
[0052] Figure 13 is a schematic diagram of another light-emitting substrate provided in an embodiment of this disclosure;
[0053] Figure 14 is a schematic diagram of another light-emitting substrate provided in an embodiment of this disclosure;
[0054] Figure 15 is a schematic flowchart of a method for preparing a light-emitting substrate according to an embodiment of the present disclosure;
[0055] Figure 16 is a schematic flowchart of another method for preparing a light-emitting substrate provided in an embodiment of this disclosure;
[0056] Figure 17 is a schematic diagram of the structure of a display device provided in an embodiment of this disclosure. Detailed Implementation
[0057] To make the objectives, technical solutions, and advantages of the embodiments of this disclosure clearer, the technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this disclosure. Furthermore, the embodiments and features in the embodiments of this disclosure can be combined with each other without conflict. All other embodiments obtained by those skilled in the art based on the described embodiments of this disclosure without creative effort are within the scope of protection of this disclosure.
[0058] Unless otherwise defined, the technical or scientific terms used in this disclosure shall have the ordinary meaning understood by one of ordinary skill in the art to which this disclosure pertains. The terms “first,” “second,” and similar terms used in this disclosure do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as “comprising” or “including” mean that an element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as “connected” or “linked” are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect.
[0059] It should be noted that the dimensions and shapes of the figures in the accompanying drawings do not reflect actual proportions and are intended only to illustrate the content of this disclosure. Furthermore, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout.
[0060] In related technologies, direct-lit backlight modules require numerous homogenizing film layers to achieve uniform light source illumination, resulting in a thicker backlight module and reduced overall luminous efficiency. To ensure uniform brightness while reducing module thickness and power consumption, many backlight module manufacturers use ink printing to create a uniformly thick reflective layer on the diffuser plate directly above the lamp panel. This layer reflects light and provides light shielding, improving light utilization. However, the improvement in homogenization is still limited. Because the reflective layer has a consistent thickness across different locations, the ratio of reflected to transmitted light of varying intensities emitted by the light-emitting device is the same. This makes it difficult to control the reflectivity and size of the reflective layer. If the overall reflectivity is too high, less light from directly above the light-emitting device will be reflected, resulting in a dim shadow (mura) above the device. Conversely, a smaller reflectivity will result in a brighter shadow (mura). The size of the reflective layer also affects the shadow (mura) in the same way.
[0061] This disclosure provides a light-emitting substrate, as shown in Figures 1 and 2, the light-emitting substrate comprising:
[0062] Base 1;
[0063] Multiple light-emitting units 2 are located on one side of the substrate 1;
[0064] The diffuser plate 3 is located on the side of the multiple light-emitting units 2 that is away from the substrate 1;
[0065] Multiple reflective portions 4 are located on the side of the diffuser plate 3 facing multiple light-emitting units 2 or on the side of the diffuser plate 3 away from the substrate 1; one light-emitting unit 2 corresponds to one reflective portion 4; the surface 401 of the reflective portion 4 away from the diffuser plate 3 is a convex surface that protrudes towards the side away from the diffuser plate 3, and the thickness of the reflective portion 4 is the greatest at the axis of symmetry perpendicular to the substrate 1.
[0066] It should be noted that, as shown in Figures 1 and 2, arrows represent light rays and their propagation directions. When the light emitted from the light-emitting unit 2 at a positive angle passes through the reflector 4 above it, part of the light will pass through the reflector 4, a small portion of the light will be blocked (absorbed) by the reflector 4, and a large portion of the light will be reflected by the reflector 4 back to the substrate 1 and then reflected again for reuse. This reflected light will continue to be reflected after passing through the substrate 1 to the area above the light-emitting unit 2, thus improving the uniform light effect of the light-emitting substrate.
[0067] The light-emitting substrate provided in this embodiment increases light utilization and improves light uniformity by providing a reflective portion. Furthermore, the surface of the reflective portion facing away from the diffuser plate is a convex surface protruding towards the diffuser plate, and the reflective portion has its maximum thickness at the axis of symmetry perpendicular to the substrate, meaning it has a shape that is thicker in the middle and thinner at the edges. Thus, when light emitted from the light-emitting unit passes through the reflective portion, more light in areas of higher intensity is reflected and absorbed, while less light in areas of lower intensity is reflected and absorbed. This increases luminous efficacy and makes the emitted light brightness of the light-emitting substrate more uniform, further improving the light uniformity. This significantly reduces the number of light-uniforming or diffuser films with light-uniforming functions in the light-emitting substrate, thereby reducing the substrate thickness and cost. Moreover, the increased luminous efficacy of the light-emitting substrate also reduces power consumption.
[0068] In some embodiments, as shown in FIG1, a plurality of reflective portions 4 are located on the side of the diffuser plate 3 facing a plurality of light-emitting units 2.
[0069] Alternatively, in some embodiments, as shown in FIG2, a plurality of reflective portions 4 are located on the side of the diffuser plate 3 away from the substrate 1.
[0070] In some embodiments, as shown in Figures 1 and 2, the substrate 1 includes a substrate 101. The substrate can be, but is not limited to, a glass substrate or a printed circuit board (PCB). The substrate has conductive metal films, silicon nitride or silicon oxide insulating films, and low-dielectric-constant insulating protective layers deposited through processes such as electroplating, physical vapor deposition, chemical vapor deposition, and spin coating. The metal films and insulating films are then processed through processes such as exposure and etching to form a driving circuit. The driving circuit is electrically connected to the light-emitting unit to control the light emission of the light-emitting unit. The metal film in the driving circuit has a high reflectivity, which reflects light emitted from the light-emitting unit towards the substrate side, thereby improving the utilization rate of the emitted light to a certain extent. The substrate may also include a metal backplate located on the side of the substrate away from the light-emitting unit, thereby increasing the strength of the substrate.
[0071] In some embodiments, as shown in Figures 1 and 2, the substrate 1 further includes a reflective layer 102 located on one side of the substrate 101. The reflective layer 102 may be made of, for example, one of the following: white reflective ink or a high-reflectivity reflective sheet. The white reflective ink may be made of an organic solvent containing titanium dioxide (TiO2) mixed with polymers such as acrylates, and has a high reflectivity, reaching 80% to 100%. The reflective sheet may be made of a metal material with high reflectivity. The reflective layer 102 has openings corresponding one-to-one with the light-emitting units 2. These openings expose a portion of the driving circuit structure, allowing the light-emitting units 2 to connect to the driving circuit. The reflective layer 102 can reflect light emitted from one side of the substrate 101, improving light utilization.
[0072] In some embodiments, the light-emitting unit 2 can be a Mini LED chip, a Micro LED chip, or a packaging structure thereof. For example, as shown in Figures 1 and 2, the light-emitting unit 2 includes a light-emitting chip 201 and a packaging structure 202. The light-emitting chip is used to emit light, such as blue or white light; that is, the light-emitting chip can be a Mini LED chip or a Micro LED chip. The light-emitting chip is a PN junction containing electro-optic conversion, along with the necessary driving circuitry, leads, and other functional layers fabricated on an epitaxial wafer. The packaging structure can be made of a high-transmittance, high-refractive-index material such as silicone resin. For example, silicone resin includes components such as polysiloxane, with a refractive index of 1.4–1.8 and a transmittance of 92%–100%. As shown in Figures 1 and 2, the surface of the packaging structure 202 facing away from the substrate 1 is an upwardly convex curved surface; that is, the packaging structure 202 has a convex lens shape. Of course, the surface of the packaging structure 202 facing away from the substrate 1 can also be set as a plane. The packaging structure can be used to protect the internal light-emitting chip from the influence of water, oxygen and impurities in the external environment on its performance. At the same time, it can adjust the angle of the light emitted by the light-emitting chip, improve the light efficiency and reduce light crosstalk between adjacent light-emitting units.
[0073] In some embodiments, as shown in Figures 1 and 2, the axis of symmetry 7 of the reflective portion 4 perpendicular to the substrate 1 coincides with the axis of symmetry 8 of the light-emitting unit 2 perpendicular to the substrate 1. That is, the orthographic projection of the center of the reflective portion 4 perpendicular to the substrate 1 coincides with the orthographic projection of the center of the light-emitting unit 2 perpendicular to the substrate 1. Since the reflective portion has the greatest thickness at the axis of symmetry perpendicular to the substrate, and the light intensity of the light-emitting unit is the strongest at the same axis, more light in areas with higher light intensity is reflected and absorbed by the reflective portion, while less light in areas with lower light intensity is reflected and absorbed by the reflective portion. This increases luminous efficiency and makes the emitted brightness of the light-emitting substrate more uniform.
[0074] In some embodiments, as shown in Figures 1 and 2, the orthographic projection of the light-emitting unit 2 onto the substrate 1 is located within the orthographic projection of the reflective part 4 onto the substrate 1.
[0075] It should be noted that the light-emitting range of the light-emitting unit is usually larger than its own size. Therefore, if the orthographic projection of the light-emitting unit on the substrate is located within the orthographic projection of the reflective part on the substrate, the reflection range of the reflective part can be increased, thereby further improving the light efficiency.
[0076] In some embodiments, the thickness of the reflective portion at different locations is positively correlated with the light intensity of the light emitted by the light-emitting unit at different locations on the reflective portion. That is, the thickness variation of the reflective portion matches the light intensity variation of the light emitted by the corresponding light-emitting unit. The reflective portion is thickest in the region with the strongest light intensity and thinnest in the region with the weakest light intensity. Since a thicker reflective portion absorbs more light, the amount of light absorbed at different locations on the reflective portion is positively correlated with the light intensity of the light emitted by the light-emitting unit at different locations on the reflective portion. More light is reflected and absorbed by the reflective portion in regions with stronger light intensity, and less light is reflected and absorbed in regions with weaker light intensity. This increases luminous efficiency and makes the emitted brightness of the light-emitting substrate more uniform, thus further improving the light uniformity of the light-emitting substrate.
[0077] In some embodiments, the maximum thickness of the reflective portion is greater than or equal to 5 micrometers and less than or equal to 30 micrometers, and the reflectivity corresponding to the maximum thickness of the reflective portion is greater than or equal to 50% and less than or equal to 80%. This avoids reducing light transmittance due to excessive maximum thickness of the reflective portion. It ensures both uniform light distribution and optimal light efficiency.
[0078] In some embodiments, the shape of the orthographic projection of the reflective portion onto the substrate is similar to the light emission pattern of the light-emitting unit.
[0079] Furthermore, since the thickness of the reflective portion at different locations is positively correlated with the light intensity of the light emitted by the light-emitting unit at different locations on the reflective portion, in some embodiments, as shown in Figures 3 and 4, the shape of the orthographic projection of the reflective portion 4 onto the substrate 1 is the same as the light emission pattern 9 of the light-emitting unit 2. Specifically, the shape of the orthographic projection of the reflective portion 4 onto the substrate 1 coincides with the light emission pattern of the light-emitting unit 2.
[0080] It should be noted that the light emission pattern of the light-emitting unit refers to the shape of the area of light emitted by the light-emitting unit as projected onto the substrate 1. In Figure 3, the light emission pattern 9 of the light-emitting unit is circular, and in Figure 4, the light emission pattern 9 of the light-emitting unit is rounded rectangle.
[0081] In some embodiments, the reflective portion is a pattern formed by 3D printing.
[0082] Alternatively, in some embodiments, the reflective portion is a pattern formed using processes such as exposure and development. This allows for a smoother convex surface in the formed reflective portion compared to 3D printing, thus improving light emission uniformity.
[0083] In some embodiments, the reflective portion includes a photosensitive reflective material. This allows for direct exposure and development of the reflective portion to form a pattern, eliminating the need for etching the reflective film layer, thus saving process steps and reducing costs.
[0084] In some embodiments, the reflective portion includes a negative photosensitive reflective material.
[0085] In some embodiments, the negative photosensitive reflective material is a negative photosensitive reflective ink. Negative photosensitive reflective ink includes: high-reflective ink, polymers containing titanium dioxide (TiO2) mixed with acrylates, negative photosensitive materials containing polyvinyl alcohol laurate, organic solvents, or organic solvents including other additives.
[0086] It should be noted that when the reflective part includes a negative photosensitive reflective material, the reflective part can be directly exposed and developed to form a pattern, eliminating the need for etching the reflective film layer. This saves on process steps and reduces costs. Furthermore, in the development step, the unexposed portions of the negative photosensitive reflective material are removed, while the exposed portions are retained, making it easier to manufacture reflective parts with convex surfaces.
[0087] In some embodiments, the reflective portion can be fabricated using a half-tone mask process. This involves forming a reflective material layer on a diffuser plate, exposing the reflective material layer multiple times using a mask, followed by development to form the pattern of the reflective portion. After forming the pattern of the reflective portion on the diffuser plate, it is assembled with a substrate to which the light-emitting units are bonded.
[0088] Alternatively, when the reflective portion is located on the side of the diffuser plate away from the substrate, the light from the light-emitting unit can be used to expose the reflective portion film. That is, in some embodiments, when the reflective portion is located on the side of the diffuser plate away from the substrate, the reflective portion is the pattern formed by the exposure of the light-emitting unit.
[0089] For example, the blue light emitted by the light-emitting unit (with a main wavelength of about 450 nanometers) is exposed. The negative photosensitive reflective material contains components such as polyvinyl alcohol laurate. Under the action of light, the double bonds in the molecules are opened, and cross-linking occurs between the chains, forming an insoluble network structure that is cured. The light intensity is strongest at the center directly above the light-emitting unit, and the more photocured reflective ink material there is, the stronger the light intensity becomes. As the distance from this center position decreases, the less photocured reflective ink material there is. After development and post-baking processes, a reflective part with varying thickness can be formed above the light-emitting unit.
[0090] It should be noted that if the pattern of the reflective part is made using 3D printing or half-tone mask technology and then assembled with the substrate to which the light-emitting unit is attached, alignment deviations may occur, causing the center of the light-emitting unit to not coincide with the center of the reflective part. This results in the strong light rays emitted by the light-emitting unit not being effectively reflected and utilized, significantly reducing the light uniformity effect. This will increase the difficulty of process control, lead to yield losses, and increase costs. However, when the reflective part is located on the side of the diffuser away from the light-emitting unit, and the light-emitting unit exposes the reflective part, the thickness of different positions of the reflective part is positively correlated with the light intensity emitted by the light-emitting unit at different positions of the reflective part. The area with the strongest light intensity corresponds to the thickest thickness of the reflective part, and the area with the weakest light intensity corresponds to the thinnest thickness of the reflective part. This allows for self-alignment between the light-emitting unit and the reflective part, ensuring that the center of the light-emitting unit and the center of the reflective part are completely coincident, that is, aligning the axis of symmetry of the reflective part perpendicular to the substrate with the axis of symmetry of the light-emitting unit perpendicular to the substrate. This avoids alignment deviations that affect the light uniformity effect.
[0091] In some embodiments, as shown in Figures 5 and 6, the light-emitting substrate further includes:
[0092] The diffusion layer 5 is located on the side of the diffusion plate 3 that is away from the multiple reflective parts 4.
[0093] The light-emitting substrate provided in this embodiment further includes a diffusion layer, which can further enhance the light uniformity of the light-emitting substrate.
[0094] Specifically, as shown in Figures 5 and 6, the diffusion layer 5, the diffusion plate 3, and the multiple reflective parts 4 are all located on the side of the light-emitting unit 2 away from the substrate 1.
[0095] In Figure 5, multiple reflective parts 4 are located on the side of the diffuser plate 3 away from the light-emitting unit 2, and the diffuser layer 5 is located on the side of the diffuser plate 3 facing the light-emitting unit 2.
[0096] In Figure 6, the diffusion layer 5 is located on the side of the diffusion plate 3 away from the light-emitting unit 2, and multiple reflective parts 4 are located on the side of the diffusion plate 3 facing the light-emitting unit 2.
[0097] In some embodiments, the haze of the diffusion layer 5 is greater than or equal to 50% and less than or equal to 90%; the transmittance of the diffusion layer 5 is greater than or equal to 50% and less than or equal to 95%; and the thickness of the diffusion layer 5 is greater than or equal to 5 micrometers and less than or equal to 100 micrometers.
[0098] In some embodiments, the diffusion layer material may be an ink containing a polymer such as TiO2 mixed with acrylate and an organic solvent (or some other additives), or a polymer such as a resin containing silica particles.
[0099] In some embodiments, as shown in Figures 7, 8, 9, and 10, the light-emitting substrate further includes:
[0100] The bonding structure 6 is located between the diffuser plate 3 and the substrate 1; the orthographic projection of the bonding structure 6 onto the substrate 1 surrounds the orthographic projection of the plurality of light-emitting units 2 onto the substrate 1; the bonding structure 6 includes a plurality of through holes penetrating the bonding structure 6 in a direction parallel to the substrate 1.
[0101] The light-emitting substrate provided in this embodiment bonds the diffuser plate to the substrate through an adhesive structure. However, considering the potential structural stress caused by thermal expansion and contraction of the sealed space surrounded by the adhesive structure without through holes due to high or low environmental temperatures or high or low reliability, through holes are provided in the adhesive structure to avoid the structural stress that may be caused by thermal expansion and contraction of the sealed space formed by the adhesive structure, thereby improving the structural strength and reliability stability of the entire light-emitting substrate product.
[0102] It should be noted that, in order to clearly illustrate the position of the bonding structure 6, the diffuser plate is not shown in FIG10. In some embodiments, as shown in FIG10, the light-emitting substrate includes a light-emitting area 10 and a peripheral area 11 surrounding the light-emitting area 10; the bonding structure 6 is located in the peripheral area 11.
[0103] In some embodiments, as shown in Figures 7 and 8, when the diffuser plate 3 does not include a diffuser layer on the side facing the light-emitting unit 2, the bonding structure 6 contacts the diffuser plate 3 and the substrate 1.
[0104] In some embodiments, as shown in FIG11, when the diffusion layer 5 is located on the side of the diffusion plate 3 facing the light-emitting unit 2, the adhesive structure 6 is located between the diffusion layer 5 and the substrate 1, that is, the adhesive structure 6 is in contact with the diffusion layer 5 and the substrate 1.
[0105] In some embodiments, as shown in Figures 7-8 and Figure 11, the bonding structure 6 is in contact with the substrate 101.
[0106] In some embodiments, the bonding structure is made of organic polymers such as polyurethane rubber, acrylate rubber, epoxy resin, or polyacrylic resin as a base material, combined with inert fillers such as talc, titanium dioxide, and kaolin, and further supplemented with plasticizers, solvents, and curing agents. In the direction perpendicular to the edge of the peripheral area containing the bonding structure, the width of the bonding structure is greater than or equal to 0.3 mm and less than or equal to 3.0 mm. The distance from the surface of the bonding structure facing away from the substrate to the substrate is greater than the distance from the surface of the encapsulation structure facing away from the substrate to the substrate. The difference between the distance from the surface of the bonding structure facing away from the substrate to the substrate and the distance from the surface of the encapsulation structure facing away from the substrate to the substrate is greater than or equal to 0.2 mm and less than or equal to 1 mm.
[0107] In some embodiments, among the multiple through holes located on the same side of the light-emitting area, the distance between any two adjacent through holes is the same. That is, the through holes are evenly distributed in the bonding structure, which can ensure the uniformity of the support of the bonding structure.
[0108] Considering that external forces caused by assembly deviations and structural interference may impact the diffuser plate, in some embodiments, the size of the diffuser plate is smaller than the size of the substrate, that is, the orthographic projection of the diffuser plate onto the plane perpendicular to the substrate falls into the substrate. Of course, if there is sufficient assembly space, the size of the diffuser plate can also be equal to or larger than the size of the substrate.
[0109] In some embodiments, the light-emitting area further includes a plurality of support portions located between the diffuser plate and the substrate. This can improve the support effect.
[0110] Next, the improvement of light uniformity by providing a reflective portion on the light-emitting substrate provided in the embodiments of this disclosure will be introduced. The light uniformity effects of different light-emitting substrates are shown in Figure 12. In the figure, curve a represents the light uniformity effect without a reflective portion, curve b represents the light uniformity effect with a reflective portion of uniform thickness, and curve c represents the light uniformity effect of the reflective portion provided in the embodiments of this disclosure whose thickness is positively correlated with the light intensity of the light-emitting unit. It can be seen from Figure 12 that the normalized brightness at different positions of curves a and b differs significantly, indicating poor light uniformity. Conversely, the normalized brightness at different positions of curve c differs less, indicating better light uniformity.
[0111] In some embodiments, when the light-emitting unit emits blue light, as shown in FIG13, on the side of the diffuser plate 3 and the plurality of reflective parts 4 facing away from the substrate 1, the light-emitting substrate further includes: a color transfer film 14, a diffuser film 13, a prism brightness enhancement film 15, and a dual brightness enhancement film 16. FIG13 only shows the positional relationship of one of the above-mentioned film layers. In practical applications, the positions of the above-mentioned film layers can be disordered. The thickness of the diffuser film is about 0.1 mm to 0.3 mm. The thickness of the color transfer film is about 0.2 mm to 0.4 mm. The color transfer film is, for example, a color transfer film containing phosphor or quantum dot particles. The side of the color transfer film facing the substrate can also be provided alone or in combination with the color transfer film to form a blue-transparent and red-green reflective film. The thickness of the prism brightness enhancement film is about 0.2 mm to 0.4 mm. The prism brightness enhancement film may also be a composite film of two or more prisms with perpendicularly intersecting angles. The prism brightness enhancement film and the dual brightness enhancement film can also be combined. If the light-emitting unit emits white light, the color transfer film can be removed.
[0112] It should be noted that in related technologies, as shown in Figure 14, since no reflective portion is provided, the diffuser plate 3 is relatively thick, and a relatively thick multilayer light-diffusing film 17 is included between the diffuser plate 3 and the color transfer film 14. If the light-diffusing effect still does not meet the requirements, the number of diffuser plates 3 needs to be increased. That is, in related technologies, the light-emitting substrate includes a large number of optical film layers, and the light-emitting substrate is relatively thick.
[0113] The light-emitting substrate provided in this embodiment can improve the light uniformity effect by providing a reflective part with varying thickness, thereby reducing the number and thickness of optical film layers.
[0114] In some embodiments, in order to further enhance the light uniformity effect, a thinner light uniformity film can also be provided on the side of the structure composed of the diffuser plate and multiple reflective parts away from the substrate. However, the total thickness of the light-emitting substrate is still smaller than that of the light-emitting substrate in the related technology shown in Figure 14, which can still reduce costs.
[0115] Based on the same inventive concept, this disclosure also provides a method for preparing a light-emitting substrate, as shown in FIG15, including:
[0116] S101, Provide a substrate, and arrange multiple light-emitting units on one side of the substrate;
[0117] S102. A diffuser plate is provided, and a pattern of multiple reflective portions is formed on one side of the diffuser plate; the diffuser plate and the multiple reflective portions are located on the side of the light-emitting unit away from the substrate; the multiple reflective portions are located on the side of the diffuser plate facing the multiple light-emitting units or on the side of the diffuser plate away from the substrate; one light-emitting unit corresponds to one reflective portion; the surface of the reflective portion away from the diffuser plate is a convex surface that protrudes towards the side away from the diffuser plate; the thickness of the reflective portion is the greatest at the axis of symmetry perpendicular to the substrate.
[0118] The method for fabricating a light-emitting substrate provided in this disclosure increases light utilization and improves the uniform light effect of the light-emitting substrate by forming a reflective portion on one side of a diffuser plate. Furthermore, the surface of the reflective portion facing away from the diffuser plate is a convex surface that protrudes towards the side facing away from the diffuser plate, and the reflective portion has the greatest thickness at the axis of symmetry perpendicular to the substrate, meaning the reflective portion has a shape that is thicker in the middle and thinner at the edges. In this way, when light emitted from the light-emitting unit passes through the reflective portion, more light in areas with higher light intensity is reflected and absorbed by the reflective portion, while less light in areas with lower light intensity is reflected and absorbed by the reflective portion. This increases luminous efficacy and makes the emitted light brightness of the light-emitting substrate more uniform, further improving the uniform light effect of the light-emitting substrate. This significantly reduces the number of light-diffusing films or uniform light-simulating films in the light-emitting substrate, thereby reducing the thickness of the light-emitting substrate and lowering costs. Moreover, the increased luminous efficacy of the light-emitting substrate also reduces power consumption.
[0119] In some embodiments, a pattern of multiple reflective portions is formed on one side of the diffuser plate using 3D printing or halftone masking.
[0120] In some embodiments, a pattern of multiple reflective portions is formed on one side of the diffuser plate using a 3D printing process, specifically including:
[0121] The material of the reflective part is printed multiple times on one side of the diffuser plate to form a pattern of multiple reflective parts.
[0122] In some embodiments, a halftone masking process is used to form a pattern of multiple reflective portions on one side of the diffuser plate, specifically including:
[0123] A photosensitive reflective material layer is formed on one side of the diffuser plate;
[0124] The photosensitive reflective material layer is exposed multiple times using a photomask.
[0125] The exposed photosensitive reflective material layer is developed to remove the photosensitive reflective material outside the reflective parts, forming a pattern of multiple reflective parts.
[0126] In some embodiments, the photosensitive reflective material layer includes a negative photosensitive reflective material. During the development step, the unexposed portions of the negative photosensitive reflective material are removed, while the exposed portions are retained, making it easier to fabricate the convex reflective portion.
[0127] In some embodiments, the developing process is followed by a drying step on the developed structure.
[0128] It should be noted that if a pattern of multiple reflective parts is formed on one side of the diffuser plate using 3D printing or halftone masking, after forming the pattern of multiple reflective parts on one side of the diffuser plate, the process also includes assembling the structure composed of the diffuser plate and multiple reflective parts with the substrate on which the light-emitting unit is provided.
[0129] Alternatively, in some embodiments, a pattern of multiple reflective portions is formed on one side of the diffuser plate, specifically including:
[0130] A negative photosensitive reflective material layer is formed on the side of the diffuser plate opposite to the multiple light-emitting units;
[0131] Multiple light-emitting units are lit up, and the negative photosensitive reflective material layer is exposed using these multiple light-emitting units;
[0132] The negative photosensitive reflective material layer is developed to form a pattern of multiple reflective parts.
[0133] When the reflective part is located on the side of the diffuser plate away from the substrate, the reflective film layer is exposed using light from the light-emitting unit. For example, blue light (main wavelength approximately 450 nm) emitted by the light-emitting unit is used for exposure. The negative photosensitive reflective material contains components such as polyvinyl alcohol laurate. Under the action of light, the double bonds in the molecules are opened, and cross-linking occurs between the chains, forming an insoluble network structure that is then cured. The light intensity is strongest at the center directly above the light-emitting unit, resulting in more photocured reflective ink material. As the distance from this center increases, the light intensity significantly decreases, and less photocured reflective ink material is used. After development and post-baking processes, a reflective part with varying thickness can be formed above the light-emitting unit. The thickness of the reflective part at different locations is positively correlated with the light intensity emitted by the light-emitting unit at different locations on the reflective part. The area with the strongest light intensity corresponds to the thickest reflective part, and the area with the weakest light intensity corresponds to the thinnest reflective part. This allows for self-alignment between the light-emitting unit and the reflective part, ensuring that the center of the light-emitting unit and the center of the reflective part completely coincide, i.e., aligning the axis of symmetry of the reflective part perpendicular to the substrate with the axis of symmetry of the light-emitting unit perpendicular to the substrate. To avoid alignment deviations that could affect the uniform light distribution.
[0134] In some embodiments, it also includes:
[0135] An adhesive material is coated onto the substrate to form an adhesive structure; the orthographic projection of the adhesive structure onto the substrate surrounds the orthographic projection of multiple light-emitting units onto the substrate.
[0136] The diffusion plate is bonded to the substrate using an adhesive structure;
[0137] Multiple through-holes are formed in the direction parallel to the substrate, penetrating the bonding structure.
[0138] In some embodiments, if a pattern of multiple reflective portions is formed on one side of the diffuser plate using 3D printing or halftone masking, then after forming the pattern of multiple reflective portions on one side of the diffuser plate, the diffuser plate is bonded to the substrate by an adhesive structure, and multiple through holes are formed in the direction parallel to the substrate, penetrating the adhesive structure.
[0139] In some embodiments, if the reflective portion is located on the side of the diffuser plate away from the substrate, and multiple reflective portions are formed using a self-aligning process, the diffuser plate is bonded to the substrate by an adhesive structure before a negative photosensitive reflective material layer is formed on the side of the diffuser plate away from the multiple light-emitting units.
[0140] After developing a pattern of multiple reflective parts on a negative photosensitive reflective material layer, multiple through holes are formed in the direction parallel to the substrate, penetrating the bonding structure.
[0141] Therefore, during the development process of the negative photoreflective material layer, the area surrounded by the bonding structure is a sealed space, which can prevent damage to the substrate and light-emitting units from the patterning steps of the negative photoreflective material layer and the developing solution. After forming the pattern of multiple reflective parts, through holes are set in the bonding structure, which can avoid structural stress caused by thermal expansion and contraction in the sealed space of the bonding structure, thereby improving the structural strength and reliability of the entire light-emitting substrate product.
[0142] Next, taking the example of the reflector being located on the side of the diffuser plate away from the substrate, the fabrication of the light-emitting substrate will be illustrated. As shown in Figure 16, the fabrication method of the light-emitting substrate includes:
[0143] S201. Multiple light-emitting units 2 are disposed on one side of the substrate 1;
[0144] S202. An adhesive material is coated on the same side of the substrate 1 and the plurality of light-emitting units 2 to form an adhesive structure 6 surrounding the plurality of light-emitting units 2, and the diffuser plate 3 is bonded to the substrate 1 through the adhesive structure 6.
[0145] S203, A negative photosensitive reflective material layer 18 is formed on the side of the diffuser plate 3 away from the multiple light-emitting units 2;
[0146] S204. Light up multiple light-emitting units 2 and expose the negative photosensitive reflective material layer 18 using the multiple light-emitting units 2; forming an exposed area 1802 and a non-exposed area 1801; the exposed area 1802 corresponds to the reflective part.
[0147] S205. The negative photosensitive reflective material layer 18 is developed, and the exposed area 1802 is retained to form a pattern of multiple reflective parts 4.
[0148] S206. Multiple through holes 601 are formed in the direction parallel to the substrate 1 to penetrate the bonding structure 6.
[0149] In some embodiments, the method for preparing the light-emitting substrate further includes:
[0150] A diffusion layer is formed on the side of the diffuser plate that is away from the multiple reflectors.
[0151] In some embodiments, if a pattern of multiple reflective portions is formed on one side of the diffuser plate using 3D printing or halftone masking, a diffusion layer can be formed on the side of the diffuser plate opposite to the multiple reflective portions after the pattern of multiple reflective portions is formed on one side of the diffuser plate; then the structure including the diffuser plate, the diffusion layer, and the multiple reflective portions is bonded to the substrate by an adhesive structure, and multiple through holes are formed in the direction parallel to the substrate through the adhesive structure.
[0152] In some embodiments, if the reflective portion is located on the side of the diffuser plate away from the substrate, and multiple reflective portions are formed using a self-aligning process, a diffusion layer is formed on one side of the diffuser plate before the diffuser plate is bonded to the substrate by the bonding structure. Then, the structure including the diffuser plate and the diffusion layer is bonded to the substrate by the bonding structure. The diffusion layer is located on the side of the diffuser plate facing the substrate, and the diffusion layer is in contact with the bonding structure.
[0153] In some embodiments, after forming the structure including a diffuser plate and multiple reflective portions, the method further includes forming a color transfer film, a diffuser film, a prism brightness enhancement film, and a dual brightness enhancement film on the side of the structure of the diffuser plate and multiple reflective portions away from the substrate. If the light-emitting unit emits white light, the color transfer film can be removed.
[0154] In some embodiments, to further enhance the light uniformity effect, a step of providing a thinner light uniformity film on the side of the structure consisting of the diffuser plate and multiple reflective parts away from the substrate is also included.
[0155] Based on the same inventive concept, this disclosure also provides a display device, as shown in FIG17, including:
[0156] The light-emitting substrate 19 provided in the embodiments of this disclosure;
[0157] The display panel 20 is located on the light-emitting side of the light-emitting substrate 19.
[0158] In some embodiments, the display panel is a liquid crystal display panel. That is, the light-emitting substrate provided in this disclosure is disposed below the liquid crystal display panel as a backlight, and is a direct-lit backlight. Since the light-emitting substrate of this disclosure can improve light uniformity and reduce module thickness, it can provide high-quality backlight for the liquid crystal display panel, thereby improving display performance and reducing power consumption.
[0159] In some embodiments, as shown in FIG17, the display panel 20 includes an array substrate 2001 and a counter substrate 2002 disposed opposite to each other, and a liquid crystal layer 2003 located between the array substrate 2001 and the counter substrate 1902.
[0160] For example, the array substrate includes a control circuit, and the opposing substrate includes a color filter. The control circuit in the array substrate can control the deflection direction of liquid crystal molecules in the liquid crystal layer, modulating the transmittance and reflectance of incident light, thereby changing the brightness and contrast of the displayed image. Light is converted into the desired color by the color filter in the opposing substrate, forming a colored display image. Polarizers can also be placed on both sides of the display panel to improve the quality of the displayed image. It is understood that the specific composition of the display panel can be designed according to actual needs, and this disclosure does not limit it.
[0161] The display device provided in this disclosure includes any product or component with a display function, such as a mobile phone, tablet computer, television, monitor, laptop computer, digital photo frame, or navigator. Other essential components of this display device are understood by those skilled in the art and will not be described in detail here, nor should they be construed as limiting this disclosure. Implementation of this display device can refer to the embodiments of the light-emitting substrate described above; repeated details will not be repeated.
[0162] In summary, the light-emitting substrate and display device provided in this disclosure improve light utilization and uniform light distribution by providing a reflective portion. Furthermore, the surface of the reflective portion facing away from the diffuser plate is a convex surface protruding towards the diffuser plate, and the reflective portion has its maximum thickness at the axis of symmetry perpendicular to the substrate, meaning it has a shape that is thicker in the middle and thinner at the edges. Thus, when light emitted from the light-emitting unit passes through the reflective portion, more light in areas of higher intensity is reflected and absorbed, while less light in areas of lower intensity is reflected and absorbed. This increases luminous efficacy and makes the emitted light brightness of the light-emitting substrate more uniform, further improving the uniform light distribution effect. This significantly reduces the number of light-diffusing films or uniform light-dispersing films in the light-emitting substrate, thereby reducing the substrate thickness and cost. Moreover, the increased luminous efficacy of the light-emitting substrate also reduces power consumption.
[0163] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention.
[0164] Obviously, those skilled in the art can make various modifications and variations to this disclosure without departing from its spirit and scope. Therefore, if such modifications and variations fall within the scope of the claims of this disclosure and their equivalents, this disclosure is also intended to include such modifications and variations.
Claims
1. A light-emitting substrate, wherein, The light-emitting substrate includes: Base; Multiple light-emitting units are located on one side of the substrate; A diffuser plate is located on the side of the plurality of light-emitting units facing away from the substrate; Multiple reflective portions are located on the side of the diffuser plate facing the multiple light-emitting units or on the side of the diffuser plate away from the substrate; one light-emitting unit corresponds to one reflective portion; the surface of the reflective portion on the side away from the diffuser plate is a convex surface that protrudes towards the side away from the diffuser plate; the reflective portion has the greatest thickness at the axis of symmetry perpendicular to the substrate.
2. The light-emitting substrate according to claim 1, wherein, The orthographic projection of the light-emitting unit onto the substrate is located within the orthographic projection of the reflective portion onto the substrate, and the axis of symmetry of the reflective portion perpendicular to the substrate coincides with the axis of symmetry of the light-emitting unit perpendicular to the substrate.
3. The light-emitting substrate according to claim 1 or 2, wherein, The thickness of the reflective portion at different locations is positively correlated with the light intensity emitted by the light-emitting unit to different locations of the reflective portion.
4. The light-emitting substrate according to claim 3, wherein, The maximum thickness of the reflective part is greater than or equal to 5 micrometers and less than or equal to 30 micrometers, and the reflectivity corresponding to the maximum thickness of the reflective part is greater than or equal to 50% and less than or equal to 80%.
5. The light-emitting substrate according to any one of claims 1 to 2, 4, wherein, The shape of the orthographic projection of the reflective part onto the substrate is similar to the light emission pattern of the light-emitting unit.
6. The light-emitting substrate according to any one of claims 1 to 2, 4, wherein, The reflective part includes a negative photosensitive reflective material.
7. The light-emitting substrate according to any one of claims 1 to 2, 4, wherein, The light-emitting substrate further includes: A diffusion layer is located on the side of the diffusion plate opposite to the plurality of reflective portions.
8. The light-emitting substrate according to claim 7, wherein, The haze of the diffusion layer is greater than or equal to 50% and less than or equal to 90%; the transmittance of the diffusion layer is greater than or equal to 50% and less than or equal to 95%; and the thickness of the diffusion layer is greater than or equal to 5 micrometers and less than or equal to 100 micrometers.
9. The light-emitting substrate according to any one of claims 1 to 2, 4, and 8, wherein, The light-emitting substrate further includes: An adhesive structure is located between the diffuser plate and the substrate; the orthographic projection of the adhesive structure onto the substrate surrounds the orthographic projection of the plurality of light-emitting units onto the substrate; the adhesive structure includes a plurality of through holes penetrating the adhesive structure in a direction parallel to the substrate.
10. A method for preparing a light-emitting substrate, wherein, The method includes: A substrate is provided, and multiple light-emitting units are disposed on one side of the substrate; The diffuser plate is provided, and a pattern of multiple reflective portions is formed on one side of the diffuser plate; the diffuser plate and the multiple reflective portions are located on the side of the light-emitting unit away from the substrate; the multiple reflective portions are located on the side of the diffuser plate facing the multiple light-emitting units or on the side of the diffuser plate away from the substrate; one light-emitting unit corresponds to one reflective portion; the surface of the reflective portion on the side away from the diffuser plate is a convex surface that protrudes towards the side away from the diffuser plate; the reflective portion has the greatest thickness at the axis of symmetry perpendicular to the substrate.
11. The method according to claim 10, wherein, The pattern of forming multiple reflective portions on one side of the diffuser plate specifically includes: A negative photosensitive reflective material layer is formed on the side of the diffuser plate opposite to the plurality of light-emitting units; The plurality of light-emitting units are lit up, and the negative photosensitive reflective material layer is exposed using the plurality of light-emitting units; The negative photosensitive reflective material layer is developed to form the pattern of the plurality of reflective parts.
12. The method according to claim 10, wherein, Multiple reflective patterns are formed on one side of the diffuser plate using 3D printing or halftone masking.
13. The method according to any one of claims 10 to 12, wherein, The method further includes: An adhesive material is coated onto the substrate to form an adhesive structure; the orthographic projection of the adhesive structure onto the substrate surrounds the orthographic projection of the plurality of light-emitting units onto the substrate. The diffusion plate is bonded to the substrate via the bonding structure; Multiple through-holes are formed through the adhesive structure in a direction parallel to the substrate.
14. The method according to any one of claims 10 to 12, wherein, The method further includes: A diffusion layer is formed on the side of the diffusion plate opposite to the plurality of reflective parts.
15. A display device, wherein, include: The light-emitting substrate according to any one of claims 1 to 9; The display panel is located on the light-emitting side of the light-emitting substrate.